For example, Japanese Patent Publication No. 4844653 discloses such a driving device in the technical field. The driving device disclosed in the Patent Publication aims to increase the rate of changing an insulated gate bipolar transistor (IGBT), as an example of semiconductor switching elements, between its switching states while limiting a surge generated due to changing of the IGBT between its switching states.
In particular, the disclosed driving device is designed as a regulated-voltage control driving device, and includes a drive circuit and a voltage controller. The drive circuit uses, as a power source therefor, an output voltage across a secondary coil of a transformer. Specifically, the drive circuit includes a regulator for regulating the output voltage across the secondary coil, and intermittently applies the regulated voltage to the on-off control terminal, i.e. the gate, of the IGBT, thus alternately turning on and off the IGBT.
The voltage controller controls a primary voltage across a primary coil of the transformer to control a value of the output voltage across the secondary coil accordingly. The drive circuit is capable of varying the rate of changing the IGBT between its switching states, i.e. on and off states, according to the controlled value of the output voltage across the secondary coil.